


Calculus

by jackles67



Category: Supernatural
Genre: Alternate Universe - High School, M/M, Sibling Incest
Language: English
Status: Completed
Published: 2013-05-23
Updated: 2013-05-23
Packaged: 2017-12-12 18:35:27
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 1,933
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/814698
Author URL: https://archiveofourown.org/users/jackles67/pseuds/jackles67
Summary: <blockquote class="userstuff">
              <p>Cas doesn't pay attention in Calculus, which means he gets extra tutoring sessions with Sam Winchester. Sam's older brother takes an interest.</p>
            </blockquote>





	Calculus

**Author's Note:**

> Originally written as askbox smut. This definitely has background Wincest going on. Potentially will write more in this verse (don't take me too seriously when I say that, I say it for everything I write).

Castiel’s stuck in tutoring, _again_. It’s always the same thing, ‘we know you’re smart enough to do better Castiel,’ and ‘you’re just not working to your full potential.’ Sam Winchester is a full two years younger than Castiel, but he skipped a grade and this is Castiel’s second time taking Calculus (he skipped the final last time, better things to do on a Friday afternoon).

Tutoring is taking place at the Winchester house this time, and Cas is keeping a lookout for Sam’s older brother, Dean. Dean’s something of a legend at school, somehow simultaneously a jock _and_  a badass _and_  the teachers can’t resist his pretty green eyes and his gravelly voice calling them ‘sir’ and ‘ma’am’.

Dean strolls into the kitchen about halfway through the tutoring session to grab a beer from the fridge. Instead of walking back out the door though, he leans back against the counter and fixes Cas with an inscrutable stare, not looking away even as he tips his head back to take a long pull from his beer.

Cas can’t take his eyes off him, gaze wandering from plump lips tight against the bottle to the way the long column of his neck works as he swallows, all the way down to his one exposed collarbone. Cas is fascinated to find there are freckles there as well, and wonders how far they go, whether there are freckles on his chest, his stomach, his hipbones...

Sam clears his throat and Cas jumps, tearing his eyes away from Dean to find Sam gazing interestedly at him. He flushes slightly, reminding himself that he, Castiel, is not the type to get flustered by some guy giving his beer bottle a blowjob. Then Sam leans in, too close to be casual, too close to be anything but flirtation, and whispers against Cas’s cheek, ‘See something you like?’ It’s obvious that Dean can hear them perfectly well, so Cas doesn’t bother lowering his voice to answer.

‘Maybe.’ Dean snorts, an undignified sound, and it breaks the tension a little. He puts his bottle down and wanders out the living room, calling over his shoulder,

‘Don’t you think it’s time for a study break, Sammy?’ Sam meets Cas’s gaze, a question in his eyes, and Cas dips his head in a quick nod. Yes, it is definitely time for a break, if the tightness in Cas’s jeans is anything to go by.

He’s not sure what he’s expecting, maybe for Sam to go upstairs while he ‘takes a break’ with Dean, but that’s not what happens. Sam leads Cas into the living room and motions for him to sit on the couch beside Dean before dropping down on his other side. Cas finds himself in the middle of the two Winchesters, wondering when exactly he fell asleep and into a wet dream.

Dean’s hand slides smoothly up Cas’s thigh, while Sam is leaning in again, and then his lips are brushing the side of Cas’s neck, so softly he can’t help but arch into it, seeking more. When Dean’s clever fingers reach the hard line of Cas’s cock, he has to bite back a whimper and remind himself that he is not some blushing virgin cheerleader. Well, except the virgin part, but no one aside from Anna knows that.

Castiel pulls himself together enough to turn his head and meet Sam’s warm, willing mouth, raising one hand to twist his finger’s in Sam’s hair while the other drops to cover Dean’s fingers with his own and press down. The friction is so good, so sweet that his hips rise off the couch for a moment and he hears Dean groan.

‘So fucking hot, Cas. Knew you’d be hot, didn’t we Sam?’

Sam pulls his mouth away from Cas’s to murmur ‘Yeah, Dean,’ against Cas’s jaw. His mouth drops lower, the barest graze of teeth and tongue against his throat. Then Sam is working the buttons of Cas’s shirt open and Dean is still rubbing him through his jeans and Cas drops his head back against the couch and gulps in big lungfuls of air. Dean’s hand curls around his jaw and tugs him in for a kiss that confirms everything Cas suspected about those soft, plush lips.

Cas remembers his manners enough to drag his hand down Dean’s chest, wondering if he has time to get at least two of Dean’s shirts off before he comes. Big and surprisingly nimble fingers find their way to Cas’s nipple and his mind goes blank for a second as he bites his lip to stop from coming. Dean chuckles, a low dirty sound that goes straight to Cas’s cock.

Sam’s gotten Cas’s shirt completely open and his mouth is following its path down his body, drawing gasps and groans from Cas that he tries to muffle against Dean’s lips. Cas slides his hand lower against Dean’s chest and stomach, finally finding his belt buckle and trying to open it one-handed. He fumbles as Sam breathes hotly against his skin and wonders how they expect him to focus on so many things at once.

The concern is wiped from his mind as Dean pushes Cas’s hands away, his fingers looping easily around Cas’s wrists. Cas opens his mouth to protest but Sam and Dean are exchanging a _look_ , one that Cas can’t hope to understand. The brothers smile at each other, then turn to look at Cas, and those grins are downright hungry. Cas closes his mouth.

‘So glad you decided to have tutoring at home, Sammy.’

‘Me too, Dean. So glad.’ They’re speaking, but the words are irrelevant. What has Cas’s heart pounding is the way Dean’s voice is soft, predatory, and the way Sam is leaning forward, over Cas. Their eyes are locked on each other as they get ever closer, right there in front of Castiel, and suddenly Cas can’t breathe.

It’s one thing to grope the kid who’s flunking math together on their couch because they’re bored, but this is something else entirely. This is Dean reaching out and tugging Sam the last couple of inches and Sam’s eyes closing at his touch. This is the way their mouths fit so perfectly they have to have done this a hundred times. This is Dean stroking Sam's cheek and Sam opening his lips on a gasp.

Cas is so hard he can’t make full sentences, or, apparently, words. He lets out a strangled moan and Dean breaks away with a soft laugh.

‘C’mon Sammy, can’t leave anyone out.’

Sam smiles and leans in to kiss Cas again while Dean’s hands fall to Cas’s fly. Sam’s lips are soft and wet from Dean and Cas barely notices that his pants are open until he feels Dean’s hand on him, drawing his cock out. Cas is so hard that every gentle touch of Dean’s fingers sends a shudder through him.

Sam pulls away from the kiss to lean over Cas and kiss Dean again, sliding his hand up Cas’s thigh to tangle his fingers with his brother’s. The sight of both of them touching him, sliding their hands up his shaft to gather the precome beading at the head, sends a thrill through Cas. He’s gotten hand jobs before - they were nothing like this. He’s so overwhelmed by the sensation of their palms slipping over him that he doesn’t immediately notice how they’re slowly moving lower.

Dean breaks the kiss when the brothers are inches from Cas’s cock. He pauses, his lips hovering over the leaking head, and looks up at Castiel. Cas doesn’t get it for a second, but when he does he’s nodding so fast he might’ve sprained something. Dean smiles and presses an open-mouthed kiss just under the head of Cas’s cock, trailing his tongue down the shaft. Sam joins him, following his brother’s mouth with his own.

They both lick up the shaft to meet at the head, kissing messily against Castiel’s cock while he tries desperately not to come. He doesn’t know what he’s done to deserve this, but he really, really doesn’t want it to end. Dean’s eyes rise to meet his as those sinful lips close over the crown of Cas’s cock while Sam’s pink tongue draws patterns along the underside. Cas’s hands are balled up tight at his sides, he’s biting his lips, and he knows his cheeks are flushed red.

When his lips sink all the way to the base of Cas’s cock, Dean groans. It’s a double shot of pleasure straight to Castiel’s spine and for a moment he doesn’t see what has Dean moaning around his cock. Then Cas notices Sam’s wrist disappearing into Dean’s open pants and the thought of that big hand around Dean, the thought that Sam probably knows exactly how to please Dean has Cas struggling not to pump his hips into the wet, warm suction of Dean’s mouth.

‘C’mon Dean. Think you can get him off before I get you off?’ Sam whispers against his brother’s ear. Dean immediately picks up the pace, his lips moving fast and wet over Castiel, his tongue swirling tightly against Cas’s skin. Sam shoots Cas a quick grin then leans in and bites Dean’s throat, hard. Dean’s mouth goes slack around a moan and he comes, hips shifting into Sam’s hand.

The sight has Castiel unable to hold off and he comes with barely any warning, just a gentle shove at Dean’s shoulder. Dean, still shaking with aftershocks, just presses closer and swallows as Cas trembles and gasps his way through the blinding pleasure. When he manages to open his eyes, it’s to find Sam’s forehead pressed against Dean’s shoulder, Dean’s hand stroking Sam quick and rough. Sam comes with a shudder and a sharp exhale against his brother’s skin.

Cas lies sprawled on the couch, Sam’s head resting on his chest, Dean playing with Sam’s hair, until they hear a car pull into the driveway. It’s a messy scramble to get everything tucked away and looking presentable, then an awkward introduction to the Winchester parents. Castiel tries to be polite, though the ‘nice boy’ act feels unfamiliar. Dean offers him a ride home, and he accepts, though he only lives a few blocks away

Sam finds an excuse to accompany them. Castiel isn’t especially surprised that they make him sit in the back even though Sam’s two years younger. He doesn’t comment, doesn’t say anything in fact, waiting to see how this plays out. The brothers keep up a steady stream of banter until they reach Cas’s house. They both turn back to face him then, and Sam stops him before he gets out of the car.

‘So, we were thinking...’ Cas waits. ‘Maybe we could have tutoring at my house from now on?’ Cas shrugs. He’s pretty sure Sam isn’t talking about math. ‘I mean, that was fun, right? That was cool?’ Sam asks. He’s getting little creases on his forehead like he’s worried, and Dean gives Cas a look. ‘Yeah. Yeah, that was... fun.’ Castiel says. Understatement of the year, Cas thinks, but doesn’t say that part out loud.

Sam’s face breaks into a smile, and Dean gives Cas an approving nod. ‘So, same time next week?’ Sam asks, and Cas nods, moving to open the door. He gets out of the car before he manages to figure out what he wants to say. ‘Thank you.’ He says it to both of them, and they shoot him identical grins before the Impala peels away from the curb. Castiel wanders into his house in a happy daze, already anticipating next week.

 


End file.
